Orchids are not like houseplants, roots wander and frequently come out of the pot.
When you repot, you try to keep root damage to a minimum but that is hard to do. However, a phalaenopsis responds very well to a repot.
If you live in a cold weather climate, you repot in the spring. If you lived in Florida you could repot at anytime. The exception is in an emergency. If the plant is in trouble, repot it to save it.
I think that the best media for a beginner to use is a mixture of medium grade bark, charcoal and sponge rock.
Welcome to the forums.
